001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.collections4.map; 018 019import org.apache.commons.collections4.OrderedMap; 020import org.apache.commons.collections4.OrderedMapIterator; 021 022/** 023 * Provides a base decorator that enables additional functionality to be added 024 * to an OrderedMap via decoration. 025 * <p> 026 * Methods are forwarded directly to the decorated map. 027 * </p> 028 * <p> 029 * This implementation does not perform any special processing with the map views. 030 * Instead it simply returns the set/collection from the wrapped map. This may be 031 * undesirable, for example if you are trying to write a validating implementation 032 * it would provide a loophole around the validation. 033 * But, you might want that loophole, so this class is kept simple. 034 * </p> 035 * 036 * @param <K> the type of the keys in this map 037 * @param <V> the type of the values in this map 038 * @since 3.0 039 */ 040public abstract class AbstractOrderedMapDecorator<K, V> extends AbstractMapDecorator<K, V> 041 implements OrderedMap<K, V> { 042 043 /** 044 * Constructor only used in deserialization, do not use otherwise. 045 * @since 3.1 046 */ 047 protected AbstractOrderedMapDecorator() { 048 super(); 049 } 050 051 /** 052 * Constructor that wraps (not copies). 053 * 054 * @param map the map to decorate, must not be null 055 * @throws NullPointerException if the map is null 056 */ 057 public AbstractOrderedMapDecorator(final OrderedMap<K, V> map) { 058 super(map); 059 } 060 061 /** 062 * Gets the map being decorated. 063 * 064 * @return the decorated map 065 */ 066 @Override 067 protected OrderedMap<K, V> decorated() { 068 return (OrderedMap<K, V>) super.decorated(); 069 } 070 071 //----------------------------------------------------------------------- 072 @Override 073 public K firstKey() { 074 return decorated().firstKey(); 075 } 076 077 @Override 078 public K lastKey() { 079 return decorated().lastKey(); 080 } 081 082 @Override 083 public K nextKey(final K key) { 084 return decorated().nextKey(key); 085 } 086 087 @Override 088 public K previousKey(final K key) { 089 return decorated().previousKey(key); 090 } 091 092 @Override 093 public OrderedMapIterator<K, V> mapIterator() { 094 return decorated().mapIterator(); 095 } 096 097}